EP 0643391 B1 20000202 - Information recording media, optical disc and playback system
Title (en)
Information recording media, optical disc and playback system
Title (de)
Informationsaufzeichnungsträger, optische Platten und Wiedergabesystem
Title (fr)
Support d'enregistrement d'information, disque optique et système de lecture
Publication
Application
Priority
- JP 22168793 A 19930907
- JP 6522494 A 19940401
Abstract (en)
[origin: EP0643391A1] A CD-ROM (4 in Fig. 1) is provided with an area for forming a character/graphic pattern (14). The character/graphic pattern (14) is formed in such a way that data, which generate on the CD-ROM (4) two sorts of pit patterns having average reflectances different from each other to a perceptible extent, are respectively recorded inside and outside the character/graphic pattern (14). Unless an illegal copy disc is produced by duplicating the legal original disc of the CD-ROM (4) at a very high precision, the character/graphic pattern of the copy disc is invisibly deformed by the discrepancy between the arrangements of the pit patterns of the copy disc and the original disc (4). <IMAGE>
IPC 1-7
IPC 8 full level
G11B 7/005 (2006.01); G11B 7/007 (2006.01); G11B 7/24 (2013.01); G11B 7/24094 (2013.01); G11B 20/00 (2006.01); G11B 23/28 (2006.01); G11B 23/34 (2006.01); G11B 23/38 (2006.01)
CPC (source: EP US)
G11B 7/005 (2013.01 - EP US); G11B 7/24 (2013.01 - EP US); G11B 7/24094 (2013.01 - EP US); G11B 20/00086 (2013.01 - EP US); G11B 20/00123 (2013.01 - EP US); G11B 20/00152 (2013.01 - EP US); G11B 20/0021 (2013.01 - EP US); G11B 20/00253 (2013.01 - EP US); G11B 20/00304 (2013.01 - EP US); G11B 20/00557 (2013.01 - EP US); G11B 20/00586 (2013.01 - EP US); G11B 20/00695 (2013.01 - EP US); G11B 23/281 (2013.01 - EP US); G11B 23/34 (2013.01 - EP US); G11B 23/38 (2013.01 - EP US); G11B 7/0079 (2013.01 - EP US)
Designated contracting state (EPC)
DE GB NL
DOCDB simple family (publication)
EP 0643391 A1 19950315; EP 0643391 B1 20000202; CN 1067172 C 20010613; CN 1116759 A 19960214; CN 1143306 C 20040324; CN 1305188 A 20010725; DE 69422870 D1 20000309; DE 69422870 T2 20001005; US 5608717 A 19970304; US 5737306 A 19980407; US 5875156 A 19990223
DOCDB simple family (application)
EP 94113942 A 19940906; CN 00126891 A 19940907; CN 94116208 A 19940907; DE 69422870 T 19940906; US 30188994 A 19940907; US 350598 A 19980106; US 68968396 A 19960813